oj.uz

Submission #310794

# Submission time Handle Problem Language Result Execution time Memory
310794 2020-10-08T00:12:17 Z VROOM_VARUN Pipes (BOI13_pipes) C++14
100 / 100
 241 ms 25520 KB 
/*
ID: varunra2
LANG: C++
TASK: pipes
*/

#include <bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
  cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions

int n, m;
vector<VII> adj;
VI vals;
VI ret;
VI deg;
MPII in;

void init() {
  adj.resize(n);
  vals.resize(n);
  ret.resize(m);
  deg.resize(n);
}

void getDeg() {
  for (int i = 0; i < n; i++) {
    deg[i] = sz(adj[i]);
  }
}

void pr() {
  for (int i = 0; i < m; i++) {
    cout << ret[i] * 2 << '\n';
  }
}

void dfs(int u) {
  // debug(u);
  deg[u] = 0;
  for (auto& x : adj[u]) {
    if (deg[x.x] > 0) {
      vals[x.x] -= vals[u];
      deg[x.x]--;
      ret[x.y] = vals[u];
      vals[u] = 0;
      if (deg[x.x] <= 1) dfs(x.x);
    }
  }
}

void bad() {
  cout << "0\n";
  exit(0);
}

void solvetree() {
  getDeg();
  for (int i = 0; i < n; i++) {
    // debug(deg[i], "here", i);
    if (deg[i] == 1) {
      dfs(i);
    }
  }

  // debug(vals);
  // debug(deg);

  for (int i = 0; i < n; i++) {
    if (vals[i] != 0) {
      bad();
    }
  }

  pr();
}

void dfscyc(int u, VI& cmp) {
  deg[u] = 0;
  cmp.PB(u);
  in[u] = 1;
  for (auto& x : adj[u]) {
    if (deg[x.x] > 0) {
      dfscyc(x.x, cmp);
      break;
    }
  }
}

int get(int u, int v) {
  trav(x, adj[u]) {
    if (x.x == v) return x.y;
  }
  return -INF;
}

void solvecyc() {
  getDeg();
  for (int i = 0; i < n; i++) {
    if (deg[i] == 1) {
      dfs(i);
    }
  }

  VI cmp;

  for (int i = 0; i < n; i++) {
    if (deg[i] > 0) {
      dfscyc(i, cmp);
      break;
    }
  }

  if (sz(cmp) % 2 == 0) bad();

  int sm = 0;

  for (int i = 0; i < sz(cmp); i++) {
    if (i % 2)
      sm -= vals[cmp[i]];
    else
      sm += vals[cmp[i]];
  }

  if (sm % 2) bad();

  sm /= 2;

  ret[get(cmp.back(), cmp[0])] = sm;

  for (int i = 0; i < sz(cmp) - 1; i++) {
    int ind = get(cmp[i], cmp[i + 1]);
    ret[ind] = vals[cmp[i]] - sm;
    sm = ret[ind];
  }

  pr();
}

void solvemultcyc() { bad(); }

int main() {
// #ifndef ONLINE_JUDGE
  // freopen("pipes.in", "r", stdin);
  // freopen("pipes.out", "w", stdout);
// #endif
  cin.sync_with_stdio(0);
  cin.tie(0);

  cin >> n >> m;

  init();

  for (int i = 0; i < n; i++) {
    cin >> vals[i];
    // vals[i] *= -1;
  }

  for (int i = 0; i < m; i++) {
    int u, v;
    cin >> u >> v;
    u--, v--;
    adj[u].PB(MP(v, i));
    adj[v].PB(MP(u, i));
  }

  if (m == n - 1) {
    solvetree();
  } else if (m == n) {
    solvecyc();
  } else {
    solvemultcyc();
  }

  return 0;
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 72 ms 9592 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 53 ms 7672 KB Output is correct
14 Correct 67 ms 9080 KB Output is correct
15 Correct 74 ms 9592 KB Output is correct
16 Correct 59 ms 8288 KB Output is correct
17 Correct 73 ms 9720 KB Output is correct
18 Correct 79 ms 9592 KB Output is correct
19 Correct 80 ms 10232 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 71 ms 9592 KB Output is correct
23 Correct 54 ms 7672 KB Output is correct
24 Correct 73 ms 9592 KB Output is correct
25 Correct 57 ms 8056 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 2 ms 512 KB Output is correct
3 Correct 88 ms 13432 KB Output is correct
4 Correct 51 ms 8696 KB Output is correct
5 Correct 47 ms 8824 KB Output is correct
6 Correct 241 ms 25464 KB Output is correct
7 Correct 1 ms 384 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 384 KB Output is correct
15 Correct 1 ms 512 KB Output is correct
16 Correct 1 ms 512 KB Output is correct
17 Correct 1 ms 512 KB Output is correct
18 Correct 1 ms 384 KB Output is correct
19 Correct 1 ms 384 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 1 ms 512 KB Output is correct
22 Correct 1 ms 512 KB Output is correct
23 Correct 92 ms 13428 KB Output is correct
24 Correct 110 ms 15220 KB Output is correct
25 Correct 89 ms 13556 KB Output is correct
26 Correct 61 ms 8696 KB Output is correct
27 Correct 54 ms 8568 KB Output is correct
28 Correct 58 ms 9208 KB Output is correct
29 Correct 194 ms 21496 KB Output is correct
30 Correct 104 ms 13940 KB Output is correct
31 Correct 139 ms 19056 KB Output is correct
32 Correct 86 ms 11512 KB Output is correct
33 Correct 92 ms 15220 KB Output is correct
34 Correct 50 ms 8696 KB Output is correct
35 Correct 55 ms 8696 KB Output is correct
36 Correct 52 ms 8952 KB Output is correct
37 Correct 226 ms 25520 KB Output is correct
38 Correct 110 ms 14452 KB Output is correct
39 Correct 82 ms 10744 KB Output is correct
40 Correct 107 ms 15004 KB Output is correct
41 Correct 116 ms 18592 KB Output is correct
42 Correct 52 ms 8568 KB Output is correct
43 Correct 50 ms 8568 KB Output is correct
44 Correct 51 ms 8824 KB Output is correct
45 Correct 170 ms 21208 KB Output is correct
46 Correct 102 ms 13684 KB Output is correct
47 Correct 106 ms 15068 KB Output is correct
48 Correct 137 ms 18672 KB Output is correct
49 Correct 66 ms 10232 KB Output is correct
50 Correct 50 ms 8824 KB Output is correct
51 Correct 57 ms 8952 KB Output is correct
52 Correct 53 ms 8568 KB Output is correct
53 Correct 187 ms 21768 KB Output is correct
54 Correct 95 ms 13300 KB Output is correct